import sys
import re

#Check credit card string
def checkCreditCard(Card):
  sum = 0
  num = len(Card)
  odd = num & 1
  for digc in range(0, num):
    dig = int(Card[digc])
    if not ((digc & 1) ^ odd):
      dig = dig * 2
      if dig > 9:
        dig = dig - 9
        sum = sum + dig
        return ((sum % 10) == 0)
      
      
